Autocross or Xtreme Bilsteins ???
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Autocross or Xtreme Bilsteins ???
Hi, I recently upgraded my C4 1991 convertible suspension with 32mm front swaybar, 500-600 lbs composite springs front and rear and 4bilstein Sport shocks, all from VBP or Ecklers
The problem is I feel the car not that well planted in hardcore street driving or ocassionally on the track?
Do you guys think I should change the shocks for the Bilstein Autocross from Ecklers or the Bilstein Xtreme from VBP? Or they are way toooo hard and only for track driving? Any other suggestion without entering into the adjustable shocks world?
Thanks!!!
The problem is I feel the car not that well planted in hardcore street driving or ocassionally on the track?
Do you guys think I should change the shocks for the Bilstein Autocross from Ecklers or the Bilstein Xtreme from VBP? Or they are way toooo hard and only for track driving? Any other suggestion without entering into the adjustable shocks world?
Thanks!!!
Le Mans Master
Joined: Mar 2001
Posts: 7,999
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From: Life is just one big track event. Everything before and after is prep and warm-up and cool-down laps
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St. Jude Donor '12
Did you replace the other suspension bushings?
Ball joints, tie rod ends (front and rear), etc.
What alignment settings are you using?
What tires?
Is the car lowered?
etc
etc
etc
What does "not feeling planted" mean to you?
understeer? where do you feel it?
oversteer? where do you feel it?
wheel hop? where do you feel it?
Ball joints, tie rod ends (front and rear), etc.
What alignment settings are you using?
What tires?
Is the car lowered?
etc
etc
etc
What does "not feeling planted" mean to you?
understeer? where do you feel it?
oversteer? where do you feel it?
wheel hop? where do you feel it?
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Joined: Mar 2012
Posts: 51
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Did not replace the bushing, but they seem fine. Should I for the polyglass ones?
Ball joints are new, the other things are old..
Camber is 0 in the front and -0.25 at the back. What would you recomend?
Car is lowered 1 inch approx
I basically feel the car a little soft after 80/90 mph, in direction changes or turning hard. No extreme under or over streer.. And also no noticable wheelhop.
May the fact that it is a convertible affect dramaticaly the stiffness of the chassis in C4s?
Thanks!!
Ball joints are new, the other things are old..
Camber is 0 in the front and -0.25 at the back. What would you recomend?
Car is lowered 1 inch approx
I basically feel the car a little soft after 80/90 mph, in direction changes or turning hard. No extreme under or over streer.. And also no noticable wheelhop.
May the fact that it is a convertible affect dramaticaly the stiffness of the chassis in C4s?
Thanks!!
Le Mans Master
Joined: Oct 2007
Posts: 9,698
Likes: 3,466
From: Akron Ohio
2025 Corvette of the Year Finalist - Modified
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St. Jude Donor '09-'10-'11
Did not replace the bushing, but they seem fine. Should I for the polyglass ones?
Ball joints are new, the other things are old..
Camber is 0 in the front and -0.25 at the back. What would you recomend?
Car is lowered 1 inch approx
I basically feel the car a little soft after 80/90 mph, in direction changes or turning hard. No extreme under or over streer.. And also no noticable wheelhop.
May the fact that it is a convertible affect dramaticaly the stiffness of the chassis in C4s?
Thanks!!
Ball joints are new, the other things are old..
Camber is 0 in the front and -0.25 at the back. What would you recomend?
Car is lowered 1 inch approx
I basically feel the car a little soft after 80/90 mph, in direction changes or turning hard. No extreme under or over streer.. And also no noticable wheelhop.
May the fact that it is a convertible affect dramaticaly the stiffness of the chassis in C4s?
Thanks!!
Slot cars are actually electric powered plastic toy cars. They ride on a track that has a slot in the middle. The toy car has a pin that goes in the slot and can only go where the slot goes. When you turn the motor on the slot car rides in the slot on the track. They tend to handle very well since the slot is guiding them around the corner. If you have a really good handing car, like a Corvette, it can be compared to the toy car by how well it handles.
Le Mans Master
Joined: Dec 2002
Posts: 5,270
Likes: 3
From: Seattle Area WA
I should add, when I mean slot car it is exactly a Kubs suggested. One notable addition though, is that they have (traditionally) no suspension. So it handles great but it is very stiff.
Le Mans Master
Joined: Mar 2001
Posts: 7,999
Likes: 14
From: Life is just one big track event. Everything before and after is prep and warm-up and cool-down laps
Cruise-In III Veteran
Cruise-In IV Veteran
St. Jude Donor '12
Did not replace the bushing, but they seem fine. Should I for the polyglass ones?
Ball joints are new, the other things are old..
Camber is 0 in the front and -0.25 at the back. What would you recomend?
Car is lowered 1 inch approx
I basically feel the car a little soft after 80/90 mph, in direction changes or turning hard. No extreme under or over streer.. And also no noticable wheelhop.
May the fact that it is a convertible affect dramaticaly the stiffness of the chassis in C4s?
Thanks!!
Ball joints are new, the other things are old..
Camber is 0 in the front and -0.25 at the back. What would you recomend?
Car is lowered 1 inch approx
I basically feel the car a little soft after 80/90 mph, in direction changes or turning hard. No extreme under or over streer.. And also no noticable wheelhop.
May the fact that it is a convertible affect dramaticaly the stiffness of the chassis in C4s?
Thanks!!
raise one side up with a jack, grab a wheel at 12 and 6 o'clock (top and bottm of the wheel) try to push in at the top and pull at the bottom. then pull at the top and push at the bottom.
Did the wheel move? If so you need to change that bearing assembly.
I'd also reccomend changing the all the bushings but the ones in the differential assy (batwing). I used the poly bushings from energy suspension and it really tightened up my car.
If you can get more camber up front - do it. The -1.5 degrees is a good start. If you can't get any more leave your rear camber alone. If you can get -1.5 in the front try -.5 to -1.0 in the rear.
Keep at it you'll find something that works for you. As long as your springs aren't delamination (splintering) your shocks/springs combo is fine.
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Cruising
Joined: Mar 2011
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I have the VBP Xtreme Bilsteins. For Auto-X, they're great, I love them. (And a lot cheaper than double-adjustable QA1's.) Big difference over the stock Bilstein Z51 shocks. On the street, they are VERY rough and unforgiving. You feel every little bump and crack in the pavement, everything rattles and shakes, and RR tracks must be idled over. I don't mind driving it to/from events, occassional weekend cruises, etc... but on a daily driver, they would be torture.
As for alignment, I have front camber maxed out, but equal on both sides (drivers side was the limiting factor with all shims out), somewhere around -1.X°. And about 1/16" toe out. For the rear, about 0.3° less camber than the fronts, and about 1/16" toe in. This setup works well for me, with 275's up front and 315's in the back. This setup though, would cause accellerated wear on the inside edges of the tread if driven on the street regularly. My car had the stock Z51 suspension, stock ride height, but I also upgraded to the VBP/Addco 32mm front sway bar with poly bushings. Overall handling is pretty netural... comfortable (as in confident... not soft) and predictable. I can induce understeer if pushing into a turn too hard, and induce oversteer if over-powering out of a corner.
As for alignment, I have front camber maxed out, but equal on both sides (drivers side was the limiting factor with all shims out), somewhere around -1.X°. And about 1/16" toe out. For the rear, about 0.3° less camber than the fronts, and about 1/16" toe in. This setup works well for me, with 275's up front and 315's in the back. This setup though, would cause accellerated wear on the inside edges of the tread if driven on the street regularly. My car had the stock Z51 suspension, stock ride height, but I also upgraded to the VBP/Addco 32mm front sway bar with poly bushings. Overall handling is pretty netural... comfortable (as in confident... not soft) and predictable. I can induce understeer if pushing into a turn too hard, and induce oversteer if over-powering out of a corner.
Drifting
Joined: Mar 2009
Posts: 1,253
Likes: 4
From: East Wenatchee (2hours from n e where) WA
600/500# with hard street tires and no camber will defiantly have a hard skittery feel. Tires are the biggest variable of all. A good tire might give you the bite in the track you are lookin for. A set of hard old mediocre tires will defiantly have that bounce around on top feel.
Melting Slicks
Joined: Dec 2008
Posts: 2,772
Likes: 64
From: Mystic CT
I don't want to burst anyones bubble but springs are determined by vehicle mass and appropriate spring frequency, Roll rate by anti roll bars, transient response by dampers that are also tuned to keep the spring wheel knukle etc assmbly within the target frequency dictated by mass. Camber to get maximum contact patch considering camber gain or loss and tire construction. This is the short story and no not going to write a 20 page disertation on it LOL. Non compliant slot cars are old school stuff as there is no traction without some compliance as the tire has to be in contact with the surface to be useful and every road / track is not pool table smooth all the way around it.
Last edited by ddahlgren; Mar 23, 2012 at 03:30 PM.
Thread Starter
Advanced
Joined: Mar 2012
Posts: 51
Likes: 0
Thread Starter
Advanced
Joined: Mar 2012
Posts: 51
Likes: 0
Have you checked your wheel bearings?
raise one side up with a jack, grab a wheel at 12 and 6 o'clock (top and bottm of the wheel) try to push in at the top and pull at the bottom. then pull at the top and push at the bottom.
Did the wheel move? If so you need to change that bearing assembly.
I'd also reccomend changing the all the bushings but the ones in the differential assy (batwing). I used the poly bushings from energy suspension and it really tightened up my car.
If you can get more camber up front - do it. The -1.5 degrees is a good start. If you can't get any more leave your rear camber alone. If you can get -1.5 in the front try -.5 to -1.0 in the rear.
Keep at it you'll find something that works for you. As long as your springs aren't delamination (splintering) your shocks/springs combo is fine.
raise one side up with a jack, grab a wheel at 12 and 6 o'clock (top and bottm of the wheel) try to push in at the top and pull at the bottom. then pull at the top and push at the bottom.
Did the wheel move? If so you need to change that bearing assembly.
I'd also reccomend changing the all the bushings but the ones in the differential assy (batwing). I used the poly bushings from energy suspension and it really tightened up my car.
If you can get more camber up front - do it. The -1.5 degrees is a good start. If you can't get any more leave your rear camber alone. If you can get -1.5 in the front try -.5 to -1.0 in the rear.
Keep at it you'll find something that works for you. As long as your springs aren't delamination (splintering) your shocks/springs combo is fine.
Regarding the 1.5 camber, wont' it wear out too much the inner part of my tires? Or this will happen only with more aggressive cambers??
